Feeding device for filing and sawing machines



July 14, 1942. V o. RICHTER FEEDING DEVICE FOR FILING AND SAWING MACHINES Filed April '7, 1941 lnvenlar: OTTQ E/CHTEE, W

' Wild/0074;

Patented July 14, 1942 FEEDING DEVICE FOR FILING AND SAWING MACHINES Otto Richter, Gary, Ind.

Application April 7, 1941, Serial No. 387,343

12 Claims.

In accordance with the present invention there are provided safety means for protecting workers engaged in the finishing of small metal pieces.

For the more accurate finishing of smaller metal pieces, particularly dies, it is customary to use filing and sawing machines by means usually falling off, nevertheless sometimes adhere to the interstices in the band and accumulate in patches which cause an uneven surface on the band and an additional resistance against the pressure exerted by the operators hand resulting in a sudden shock that may cause the operators hand to slip and become injured by its coming into contact with the band.

The present invention has for its important object the provision of a safety feeding mechanism for interposition between the metal piece and operator's hand, while at the same time affording sufficient pressure on the metal piece being worked to maintain the proper working engagement between it and the teeth of the band.

A further object of the invention is to provide a mechanism of the above indicated character which will yield readily under additional resistance exerted by accumulated refuse in the band without transmitting substantial additional pressure on the operators hand.

Further objects of the invention will become apparent as the description proceeds, and the features of novelty will be pointed out in particularity in the appended claims. It will be understood that the description and drawing attached hereto are to be regarded as illustrative only of a form of the invention, it being intended to include within its scope such modifications, changes, and rearrangement of parts as may be necessary to adapt the construction to varying conditions and uses as will be defined by the appended claims.

The invention will be understood more clearly by reference to the accompanying drawing which illustrates a preferred form of the improved device, and wherein- Figure 1 is a sectional elevation of the improved construction showing it in operative position;

Figure 2 is a transverse sectional elevation through the improved construction taken along Y the line II-II of Figure 1 looking in the direction of the arrows, and showing certain details of the mounting; and

Figure 3 is an enlarged longitudinal sectional elevation of the improved construction showing additional structural details and the action of the device under pressure exerted by accumulated metal particles adhering to the filing band.

Referring more particularly to the drawing, A represents a rapidly rotating sheave which rotates an endless serrated or toothed steel band B operating on a metal part such as a metal die indicated at C. The improved mechanism is indicated generally at D.

This improved mechanism comprises a handle 5 which is hingedly mounted at I to a bracket 9 projecting from a holder II which is attached firmly, as is indicated at I3, to the filing machine table l5.

The handle 5 has a hole I! extending through it, this hole being adjacent to the hinge I and being rather large so as to encase a sleeve H], which is held in the handle .5 by suitable pins illustrated at 2| and 23 in Figure 2. These pins allow the sleeve I9 to swing freely in the handle 5, the movability of the handle 5 and the sleeve [9 enabling the device to be used with many different sizes of metal parts being Worked.

Within the sleeve Hi there is fitted a rod 25 which extends into the sleeve l9 sufiiciently far to be retained therein while bearing against the metal part C at substantially right angles thereto, while its inner end engages a plunger 22. This plunger 22 is outset at its outer end to a larger diameter, as is indicated at 21, an annular groove 29 being cut into this enlarged portion. In this groove there is slipped an annular spring 3| made from suitable material such as hardened steel wire.

A nut 33 is threaded on the end of the sleeve #9, the nut defining an annular space 35 therein which retains the spring 3|, and the outer end of the plunger 22 terminates in a large head 37. The plunger 22 is locked by means of this spring 3| between the sleeve l9 and the nut 33, and is retained in the sleeve l9 by a retaining pin 39 mounted on the interior of the sleeve and extending into slot 4| extending longitudinally of the plunger 22.

When the improved device is to be operated, the rod 25, which is of suitable length, is slipped into the forward part of the sleeve and against the plunger 22. Through the leverage between the locking pins 2|, 23 at the bottom of the handle and the sleeve l9, the operator exerts a pressure on the workpiece C which is being filed by the band B, the pressure being sufficient to hold the workpiece C against the band B, but less than the pressure which is required to open the circular spring 3|.

However, in the event that metal particles abraded by the file accumulate on the surface of the filing blades of the band B, and thus increase the pressure between the band B and the workpiece C to such an extent as would tend to stall the machine, this pressure, before it has reached the stalling point, will cause the circular spring 3! to open up out of the groove 29 and the plunger 22 to slip backwards from the position shown in Figure 1 to that indicated in Figure 3, thereby releasing the pressure completely. The cutting machine A then is stopped and accumu' lated dust particles are cleaned off. The spring Si is snapped back into the groove 29 by pressing on the plunger head 3'! and the operation is continued.

It will be apparent of course that many varia tions in theconstruction herein illustrated and described will suggest themselves readily without in any way departing from the spirit and scope of the invention, an important feature of the construction being the spring which normally locks the plunger in the handle so that from a safe distance an operator can force the workpiece to-be filed or sawed or otherwise worked, against the rotating band through pressure applied to the workpiece through the holding rod, but will permit this red and the plunger to snap backwards when accumulation on the band might affect the accuracy of the work to be performed or cause a slippage of the material.

I claim:

1. Feeding mechanism for feeding a workpiece into operative engagement with working means, comprising the combination with a table, of mounting means on the table, a handle device remote from the workpiece and hingedly secured to the mounting means for selective movement towards and away from the workpiece, and pressure applying mechanism carried by the handle and. adapted to engage the workpiece under pressure applied thereto from the handle, the said mechanism comprising means for engaging the workpiece to feed the same to the working means, instrumentalities normally rigidly engaging the said means for maintaining feeding engagement thereof with the workpiece, and quick-acting means enabling the said instrumentalities automatically to yield under transmission thereto of pressure above the yield point of the said means, thereby releasing the workpiece from working engagement with the working means while obviating manual handling of the workpiece while in proximity to the working means.

2. Feeding mechanism for feeding a workpiece into operative engagement with working means, comprising the combination with mounting means, of a lever hingedly mounted on the mounting means, a sleeve pivotally mounted on the lever, a plunger in the sleeve, 2. rod in the sleeve engaging the plunger and adapted to engage the workpiece for feeding the same to the working means under pressure applied to the lever, and locking means for the plunger, the said locking means being yieldable under excess pressure applied to the workpiece by the working means, thereby causing the rod and plunger to retract and release the workpiece from working engagement with the working means, the said lever being positioned sufficiently away from the workpiece and working means to afford a safe working station for an operator and obviating manual handling of the workpiece in proximity to the working means.

3. Feeding mechanism for feeding a workpiece into operative engagement with working instrumentalities, comprising the combination with mounting means, of a lever hingedly mounted on the mounting means, a sleeve pivotally mounted on the lever, a plunger in the sleeve, a rod in the sleeve engaging the plunger and adapted to engage the workpiece for feeding the same to the working means under pressure applied to the lever, an annular spring engaging the plunger, and means for locking the spring and plunger, the said spring being releasable under excess pressure imparted to the workpiece by the working instrumentalities, thereby causing the plunger to snap back to release said pressure and workpiece from the working instrumentalities while avoiding manual handling of the workpiece in proximity to the working instrumentalities.

4. Feeding mechanism for enabling an operator to feed a workpiece into operative engagement with working instrumentalities from a station remote therefrom, comprising, in combination, a holding rod for exerting feeding pressure on the workpiece to maintain it in working engagement with the working instrumentalities, a holder for the rod, means normally urging the rod into feeding engagement with the workpiece, and yieldable locking instrumentalities for maintaining the rod in rigid feeding position while enabling the rod instantaneously to yield responsive to pressures exerted thereon greater than the yield point of the locking instrumentalities for effecting release of the workpiece from working engagement with the working instrumentalities, while obviating manual handling of the workpiece in proximity to the working instrumentalities.

5. Feeding mechanism for enabling an operator to feed a workpiece into operative engagement with working instrumentalities from a station remote therefrom, comprising, in combination, holding means for the workpiece, means for receiving the holding means, yieldable snap acting locking instrumentalities for the holding means adapted to release the holding means responsive to application to the workpiece of a pressure greater than the yield point of the looking instrumentalities, thereby causing the holding means to yield to release the workpiece from engagement with the working instrumentalities, and mounting means for the holding means at a station remote from the workpiece and working instrumentalities, the said mounting means transmitting feeding pressures to the holding means and workpiece less than the pressure required to actuate the locking instrumentalities.

6. Feeding mechanism for enabling an operator to feed a workpiece into operative engagement with working instrumentalities from a station remote therefrom, comprising, in combination, holding means for the workpiece, means for retaining the holding means, yieldable locking instrumentalities for the holding means including a spring normally locking the said holding means rigidly in the retaining means, and mechanism remote from the workpiece for pressing the holding means against the workpiece to feed the same to the working instrumentalities, the said spring enabling the holding means to yield instantaneously responsive to application of pressures thereto greater than the yield point of the spring, thereby releasing the said pressures without danger of injury to the operator.

7. Feeding device for filing and sawing machines including a rotating cutting band adapted to operate on a metal part, which comprises, in combination, a holding rod adapted to press the said part against the band, a sleeve for receiving the holding rod, a plunger in the sleeve engaged by the said rod, means including a locking spring adapted to lock the plunger in rigid position for maintaining the holding rod in engagement with the metal piece, and operating instrumentalities for the rod and sleeve remote from the metal part for maintaining the rod in feeding engagement with the said part, the said spring being yieldable under increased pressure on the rod to enable the rod and plunger to be retracted to release the pressure and metal part without injury to an operator.

8. Feeding device for filing and sawing machines including a rotating cutting band adapted to operate on a metal part, which comprises, in combination, a holding rod adapted to press the said part against the band, a sleeve for receiving the holding rod, a plunger in the sleeve engaged by the said rod, means including a locking spring adapted to lock the plunger in rigid position for maintaining the holding rod in engagement with the metal piece, an operating lever for the rod and sleeve remote from the metal part for maintaining the rod in feeding engagement with the said part, the spring being yieldable under increased pressure on the rod to enable the rod and plunger to be retracted to release the pressure and metal part without injury to an operator, and means for pivotally mounting the said sleeve on the operating lever.

9. Feeding device for filing and sawing machines including a rotating cutting band adapted to operate on a small part, which comprises, in combination, a retractable holding rod adapted to press the said part against the band, a sleeve for receiving the rod, means for mounting the rod yieldably with respect to the sleeve, the said means including a yieldable spring normally holding the rod in rigid position with respect to the part but allowing the rod to retract instantaneously responsive to exertion thereon of pressures in excess of the yield point of the spring thereby releasing the said pressure and part, and operating instrumentalities for the rod and sleeve for pressing the rod in feeding engagement with the said part.

10. Feeding device for filing and sawing machines including a rotating cutting band adapt-v ed to operate on a metal part, which comprises the combination with a mounting table, of mounting means on the table, a lever hingedly mounted on the mounting means remote from the cutting band and metal part, a hinge connection between the lever and mounting means, an opening through the lever adjacent to the hinge connection, a sleeve in the said opening at least substantially enclosed by the lever, means for pivotally connecting the sleeve to the lever, plunger mechanism in the sleeve including a rod normally held in feeding engagement with the part by pressure transmitted thereto from the lever, and yieldable locking means for the plunger mechanism adapted to allow the said mechanism to snap backwards under pressures exerted on the metal part in excess of the yield point of the looking means, thereby releasing the said pressure and part without danger of injury to an operator.

11. Feeding device for filing and sawing machines including a rotating cutting band adapted to operate on a metal part, which comprises the combination with a mounting table, of mounting means on the table, a lever hingedly mounted on the mounting means remote from the cutting band and metal part, a hinge connection between the lever and mounting means, an opening through the lever adjacent, to the hinge connection, a sleeve in the said opening at least substantially enclosed by the lever, means for pivotally connecting the sleeve to the lever, plunger mechanism in the sleeve including a rod normally held in feeding engagement with the part by pressure transmitted thereto from the lever, yieldable locking means for the plunger mechanism adapted to allow the said mechanism to snap backwards under pressure exerted on the metal part in excess of the yield point of the locking means, thereby releasing the said pressure and part without danger of injury to an operator, and means enabling the plunger mechanism to be returned readily to locked position.

12. Feeding device for vfiling and sawing machines including a rotating cutting band adapted to operate on a metal part, which comprises a yieldably mounted plunger mechanism, a housing for the mechanism, a spring for releasably locking the plunger mechanism in feeding engagement with the metal part, and operating means for the plunger mechanism enabling an operator from a safe distance to force the metal part against the cutting band while enabling the plunger mechanism to snap backwards responsive to pressures exerted on the part in excess of the yield point of the spring, thereby releasing the metal part from engagement with the band.

OTTO RICHTER. 

